Sub‐seasonal predictability of the 2017–2018 Southern Hemisphere tropical cyclone season.

Multi‐week forecasts of tropical cyclone genesis are evaluated for the 2017–2018 Southern Hemisphere cyclone season. These forecasts were created with the Australian Bureau of Meteorology's new seasonal forecast system, ACCESS‐S. Forecast performance over the season showed positive Brier Skill Scores with good forecast reliability and improved skill over climatology out to week 3. ACCESS‐S provided guidance of the formation of major cyclone events during the season at more than 2 weeks lead time, including Cyclone Gita in the South Pacific which later devastated Tonga, and the landfall of Cyclone Hilda in western Australia. Multi‐week forecasts of tropical cyclone genesis are evaluated for the 2017–2018 Southern Hemisphere cyclone season. These forecasts were created with the Australian Bureau of Meteorology's new seasonal forecast system, ACCESS‐S. Forecast performance over the season showed positive Brier skill scores with good forecast reliability and improved skill over climatology out to week 3. ACCESS‐S provided guidance of the formation of major cyclone events during the season at more than 2 weeks lead time, including Cyclone Gita in the South Pacific. [ABSTRACT FROM AUTHOR]